1. Field of Endeavor
The present invention relates to engines and more particularly to Homogeneous Charge Compression Ignition (HCCI) Engines.
2. State of Technology
U.S. Pat. No. 4,769,995 issued Sep. 13, 1988 for an air-fuel ratio controller for a turbocharged internal combustion engine to J. Vincent Serve and David W. Eckard and assigned to Cooper Industries, Inc. provides the following state of technology information, “A conventional air-fuel ratio controller regulates air-to-fuel ratio by controlling air manifold pressure as a function of gas manifold pressure and engine speed. While such a controller maintains a relatively constant air-to-fuel ratio for a wide range of loads, the ratio provided by such a controller occasionally deviates from an optimum value. One such occasion arises when fuel heating values vary. Accordingly, a need for an air-fuel ratio controller which is capable of correcting for varying fuel heating values has been recognized.”
U.S. Pat. No. 5,285,756 issued Feb. 15, 1994 for a gaseous fuel injection valve and actuator to Vaughn A. Squires and assigned to Cooper Industries, Inc. provides the following state of technology information, “In the operation of reciprocating engines that operate by internal combustion of gaseous fuels as natural gas, fuel injection valves are critical to smooth operation of the engine. Typically, each cylinder of such a reciprocating engine has a fuel injection valve communicating therewith, the operation of the fuel injection valve necessary for smooth, efficient operation of the engine.”
U.S. Pat. No. 6,260,520 Homogeneous charge compression ignition internal combustion engine issued Jul. 17, 2001 to Larry Van Reatherford and assigned to Ford Global Technologies provides the following state of technology information, “The HCCI engine offers tantalizing potential for low hydrocarbon emissions and low NOx emissions coupled with significant fuel economy improvement. Unlike its better known compression ignition cousin, the diesel engine, the HCCI engine may be operated soot free and also with low NOx emissions because there is no locally rich zone of combustion. Rather, ignition occurs spontaneously and concurrently at many points in the combustion chamber. A problem heretofore, however, has resided in the lack of capability to precisely control the onset of the ignition event. The present invention solves this problem. Another problem with previous HCCI engines was the apparent inability to operate satisfactorily on fuels having a wide range of cetane or octane ratings. An engine according to this present invention has adaptable timing capability which will allow fuel quality to be accurately and adequately handled.”
U.S. Pat. No. 6,390,054 issued May 21, 2002 for engine control strategy for a hybrid HCCI engine to Jialin Yang and assigned to Ford Global Technologies, Inc. provides the following state of technology information, “The HCCI engine is a relatively new type of engine. It has the benefits of very low NOx emissions due to the low combustion temperatures of the diluted mixture, and zero soot emissions due to the premixed lean mixture. Also, thermal efficiency of the HCCI engine is higher than SI engines and is comparable to conventional compression ignition engines due to the high compression ratio, unthrottled operation, high air-fuel ratio, reduced radiation heat transfer loss, and the low cycle-to-cycle variation of HCCI combustion.”
U.S. Patent Application No. 2002/0059907 published May 23, 2002 for homogenous charge compression ignition and barrel engines by Charles Russell Thomas provides the following state of technology information, “Another combustion strategy, referred to herein as homogenous charge compression ignition (HCCI) . . . In HCCI, a mixture of air and fuel is drawn into a combustion cylinder. The mixture is then compressed until the mixture autoignites, without the introduction of a spark. Variations on HCCI include injection of fuel directly into the cylinder at some point during the compression stroke so as to promote a substantially premixed charge. The HCCI combustion strategy has been referred to by various names, including controlled auto-ignition combustion (Ford), premixed charged compression ignition (Toyota and VW), active radical combustion (Honda), fluid dynamically controlled combustion (French Petroleum Institute), and active thermo combustion (Nippon Engines).”